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View Full Version : Fuel tank removal, 95 Sub



moondoggie
09-18-2008, 07:33
Good Day!

What tricks do I need to know to drop my tank? It has < 18 gallons of fuel in it, which is convenient - I have a 6 gallon gas can I can empty & use, so I'll only have to buy 2 more, plus it appears there's no anti-siphon hardware in the fill tube, like the gassers have.

I have to fix a fuel line leak, & it looks like dropping the tank is the best way to make a quality repair. It leaks where the rubber hose from the top of the tank is crimped to the steel line that heads forward. It's clamped to the frame rail, & I'm not a good enough mechanic to work in that cramped of a space. (Kinda interesting - this is how the oil lines on both my trucks have failed... :()

BTW, I was finally forced to try an idea I had some years ago. This leak was leaking air into the fuel line, so very erratic-running engine. How to find air leaking INTO a fuel line? I bought a cheapo gas cap, removed the pressure / vacuum regulating parts & the handle you turn to remove or tighten the gas cap. There was a hole in the center of the threaded piece just the right size to push a brass 1/8 NPT fitting into, with a little slop. (I used 2 male / female adapter fittings to do this.) So, I put a washer & o-ring on the male end of the 1st fitting, pushed it through the hole in the gas cap part, & threaded the other fitting onto it. When I'd tightened the fittings enough to not leak, the o-ring was compressed just right to seal too. I then connected this rig to my air compressor. I turned the compressor on just enought to make the gauge come off the pin, maybe 2 PSI, threaded my rig into the tank fill hole, & opened the valve on the compressor. The tank popped a little, but nothing was damaged. The leak became glaringly obvious, which was just what I needed.

It occurred to me later that maybe the same thing could have been accomplished more simply & with zero likelihood of blowing up the fuel tank, but I didn't try this. If I'd simply parked the Sub out of the shade, loosened then re-tightened the fuel cap at the coolest part of the day, & wait for the sun to heat it up, that should pressurize the tank too. In this case, the fuel cap would regulate the pressure, so no chance of blowing anything up. Hmmm....next time, I guess.

Thanks & Blessings!

“If an associate asks for loyalty, give him integrity; if he asks for integrity, give him loyalty.” John Boyd

DennisG01
09-18-2008, 11:46
I haven't looked on mine, but by any chance is there an access plate in the cargo area? Maybe just take a quick look from underneath.

moondoggie
09-18-2008, 12:10
Good Day!

Trouble is, the leak is where the rubber tube is swaged to the steel tube in the driver-side frame rail. I simply need the tank out of the way so I can get at what needs fixing. As far as I know, there's nothing wrong on the top of the tank, but of course I'll be looking everything there over carefully.


Thanks & Blessings!
(signature in previous post)

DennisG01
09-19-2008, 05:18
Oh, I see. You mentioned that in your first post, but I guess I didn't put two and two together in regards to where the actual problem was.

I did a quick search in the 6.5 section and the first result was a guy (94suburban) who has recently dropped his tank. It doesn't appear he's on this forum all too often, but maybe a PM or direct e-mail (if he lists it) would be in order.

http://www.thedieselpageforums.com/tdpforum/showthread.php?t=32774&highlight=fuel+tank+removal

MikeC
09-21-2008, 09:25
Moondoggie,

I used to have a 96 Burban with a 6.5. I had to drop the tank to put a new sending unit in it. I supported the tank with a floor jack and a short 2x12 to protect the tank. Loosened the straps and slowly lowered the tank. There was plenty of reach on everything and the removal is pretty straightforward.

Good luck!

Mike

moondoggie
09-22-2008, 04:33
Good Day!

That's what I was hoping to hear - thanks!

I was hoping to get this done this weekend, but other things popped up, so I don't know when I'll get to it. It's good to have a spare vehicle. ;)

Blessings!
(signature in previous post)

DieselDavy
09-22-2008, 06:18
Moondoggie,
When I last took my tanks down on my pickup, I ordered new tank straps/hardware from LMC Truck. I'm sure I had less than $75 per side. They even had the 'tar paper like' padding to put in between the straps and the tank. This removes the worries of removing the straps down with out breaking the rusted bolts or deforming the straps. You might want to look into this. I know you are somewhat thrifty, (ok, you're a tight wad, no shame in that!) but if you find the straps are rusted or the bolts are too corroded to remove, you'll be setting there with the tank down for a while you find parts!
While I was at it, I killed all the rust on the tanks and coated them to help push out the time 'till I had to do this again.
I was originally removing the tanks to repair a fuel pickup in one tank and a leak in the other, while in there, I inspected everything and replaced any lines that looked suspicious.
Works like a champ now!
Good luck,
Dave

CaptnPea
04-18-2009, 08:45
Ok...

I have the exact same problem... and I agree getting to the fittings with the tank there is just too tight for me, so "I'll just drop the tank".

BUT... get this empty tank, loosen the straps, nothing moves. So I removed them completely and took off the plastic tank shield... look for something else holding the tank up, nothing there.

Now I have pushed, pulled, pried, banged on... can't get the thing to budge??? What the heck???

Anyone have a good idea what to do next?

Warren96
04-29-2009, 06:44
There are tar like anti squeek shims on the top and sides of the tank that are probably sticking it to the frame. Removing all of the fuel is definatley the way to go before you lower it. I have had mine off a couple of times, and EMPTY was always best. Can you see from the side that there is an anti rust material on the ring that holds the sending unit in? MAKE SURE YOU REPLACE IT! I covered the ring, the steel fuel lines and most of the top of the tank with it.